I put handfuls of bird grit in my filter. It's probably a bit used up now though, hehe...But it should slowly increase the PH and it should only slowly drop once it starts getting used up.
Should be ok, the method they use for producing the oxygen, I believe, results in it being pretty pure regardless of what grade it is. Especially with pure oxygen which can make nearly anything burn.
Are you using the air pump to just inflate bags or actually airating it?
Anyway, just an inflated bag with little water and just one small fish should be good for 12+ hours easy. Bigger fish, smaller bag=less time.
Like the previous 3-4 threads in the last month asking this question, yes it's perfectly fine. May raise your PH a little bit if there's heaps of shell in it, I haven't noticed any sand around that I've seen having any worth worrying about.
I think we need to make this a sticky, along with "Is driftwood from the beach ok?"
Basically sitting around monitoring computers, some running around loading tapes, running a bit of processing. It's 12 hour shifts, 4 days nights, 4 days off, 4 days days, 4 days off.
Monkeys tend to attack people with rhesus incompatibility factor. Kids are just little ugly bald monkeys, hence the problems Caryl had when she had kids.
You could blame the poor education system, the downfall of critical thinking, the rise of "There is no wrong answer...", the widening difference in reproduction rates between the intelligent and educated vs the stupid and ignorant...Probably dozens of other factors.
Being diabetic doesn't allow you to donate blood? That's a bit odd. It's not as if it's contagious... If anything, it would lower your blood glucose level a bit.
Most of your blood is replaced every 100 or so days. If your body can't handle a little increase in that rate you have bigger problems than losing a few hundred ml of blood.